Rear deferential
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Rear deferential
Any input would be greatly appreciated guys. I currently have a 04 xlt 4.6l 2wd f150. I have been experiencing bad steering wheel vibrations at anywhere from 50mph to 65mph. It still has the vibration at other speeds but no where near as bad! I have aftermarket wheels and thought maby it was one of the wheels. I put my factory 17” back on and it still has the vibration only you cannot tell it because of the tires( the aftermarket’s have meaty all-terrains). I also noticed when I first take of there was a roaring noise coming from the back and when the vibrations start the bed of my truck is jumping pretty bad. So I came to the conclusion after I rocked the truck back and forth in the back and heard banging (like the axels moving around)that I needed to replace my axel bearings! Well I started this journey on Thursday night and today I finally got the one bearing out. I’m about to replace it but other than what’s going on with the truck my other question is the tag on my rear end had 88 on it and I thought I had a 8.8 rear end. After I pulled the bearings and saw the new ones I realized that they were to small so I went down to the parts store and they gave me 9” bearings. Why would the tag say 8.8 and the door code say 8.8 but have a 9”? Also my axel lengths are 35”and change and 36” and change I read somewhere they were only supposed to be 48” flange to flange is this for older trucks are something? Input on any are all is greatly appreciated
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Joined: Jan 2020
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From: utah
Any input would be greatly appreciated guys. I currently have a 04 xlt 4.6l 2wd f150. I have been experiencing bad steering wheel vibrations at anywhere from 50mph to 65mph. It still has the vibration at other speeds but no where near as bad! I have aftermarket wheels and thought maby it was one of the wheels. I put my factory 17” back on and it still has the vibration only you cannot tell it because of the tires( the aftermarket’s have meaty all-terrains). I also noticed when I first take of there was a roaring noise coming from the back and when the vibrations start the bed of my truck is jumping pretty bad. So I came to the conclusion after I rocked the truck back and forth in the back and heard banging (like the axels moving around)that I needed to replace my axel bearings! Well I started this journey on Thursday night and today I finally got the one bearing out. I’m about to replace it but other than what’s going on with the truck my other question is the tag on my rear end had 88 on it and I thought I had a 8.8 rear end. After I pulled the bearings and saw the new ones I realized that they were to small so I went down to the parts store and they gave me 9” bearings. Why would the tag say 8.8 and the door code say 8.8 but have a 9”? Also my axel lengths are 35”and change and 36” and change I read somewhere they were only supposed to be 48” flange to flange is this for older trucks are something? Input on any are all is greatly appreciated
2. There is supposed to be that play that you could hear when you were rocking your bed side to side. It is because there is some play in the differential where the axle retainer clips fit inside the carrier... It allowed some side to side (on the vehicle) end play.
3. You probably do have a 8.8 axle but they had different versions some with the bigger axle bearings. The easy way to tell us the 8.8 cover is mostly a square with rounded corners. The 9.75 diff cover is wider and more diamond shaped, one side is wider than the other, it's asymmetrical.
So I'm not saying your bearings couldn't be bad, but new bearings will still have the same end play they don't retain the axle shafts whatsoever in the thrust direction.
If your axle housing is bent or out of alignment or if the park brakes are not adjusted that might vibrations though...
I don't know the width flange to flange but it's more than. 48" overall the 36 and 35 sound about right.